4954-07-8Relevant articles and documents
Synthesis of [3α-3H] 17α-Hydroxy pregnenolone and [3α-3H] Pregnenolone
Tian, Yuan,Hong, Yang,Bonacorsi, Samuel J.,Balog, Aaron,Gong, Sharon
, p. 1 - 11 (2014)
For the first time, [3α-3H] 17α-hydroxy pregnenolone (1) was synthesized through a multiple step sequence. The presence of [3β-3H] isomer in RP-HPLC purified product was identified by tritium NMR. The [3β-3H] isomer was then separated from [3α-3H] 17α-hydroxy pregnenolone with chiralPAK AD-H column. [3α-3H] pregnenolone (2) was synthesized from commercial available 5-pregnen-3,20-dione in one step with an improved procedure. [3α-3H] 17α-hydroxy pregnenolone (1) was synthesized through a multiple step sequence. The presence of [3β- 3H] isomer was identified then separated with chiralPAK AD-H column. [3α-3H] pregnenolone (2) was synthesized from commercial available 5-pregnen-3,20-dione in one step. Copyright
Microwave induced selective enolization of steroidal ketones and efficient acetylation of sterols in semisolid state
Marwah, Padma,Marwah, Ashok,Lardy, Henry A.
, p. 2273 - 2287 (2007/10/03)
Under microwave irradiation steroidal enones, more specifically, position three carbonyls were efficiently and selectively converted to the corresponding enol acetates in the presence of additional enolizable carbonyl functions at other positions, using acetic anhydride and a catalytic amount of toluene-p-sulfonic acid. Acetylation of hydroxyl groups of the sterols, including those at the hindered positions, was near quantitative. Strictly anhydrous conditions were not a pre-requisite for acetylation and the reaction system easily tolerated up to 10% (v/v) moisture.
Site-Selective Fluorination of Organic Compounds Using 1-Alkyl-4-fluoro-1,4-diazabicyclooctane Salts (Selectfluor Reagents)
Lal, G. Sankar
, p. 2791 - 2796 (2007/10/02)
The new "N-F"-type electrophilic reagent family of 1-alkyl-4-fluoro-1,4-diazabicyclooctane salts (derived from elemental fluorine (F2) and 1-alkyl-1,4-diazabicyclooctane salts) has been found to be very effective for the fluorination of a wide variety of organic substrates.These include steroidal enol acetates and silyl enol ethers, phenyl-substituted olefins, sulfides bearing α-H atoms, certain carbanions, and mildly activated aromatic compounds.The products were obtained with good yields and regioselectivity under very mild reaction conditions.